1. Field Of The Invention
The present invention relates to wireline packers. More particularly, the present invention relates to a well tool, such as a packer, which may be run on a wireline and set downhole, and released using the tubing string in order to be retrieved from the well bore.
2. General Background
During the process of producing a well, there are various types of packers or packer assemblies which are utilized down the well bore. Usually, the packer is lowered into the well bore, and set within the bore in order to undertake various operations downhole, such as production of the well through the packer from a formation below the packer, or to carry out various operations below the packer, so that the operations conducted below the packer is isolated from the wellbore above the packer.
In the current state of the art, most packers which are positioned downhole require that multiple trips into and out of the well bore must be done in order to complete operations. Since the packer must first be lowered into the hole, set in place, the operations conducted, the equipment which works with the packer must be lowered into the hole, and retrieved from the hole, in separate trips. The packer, itself, must then be retrieved from the hole through a separate run downhole. Due to this multiplicity of trips required, the amount of time to conduct this procedure is very costly to the rig, and usually requires at least four workers in order to complete the operations.
One particular patent which has been granted in the art is cited in the accompanying prior art statement. U.S. Pat. No. 5,197,547, entitled "Wireline Set Packer Tool Arrangement" discloses a packer set by a well string setting tool which can converted to be run and set by a wireline setting tool which includes a body portion a collapsed spring on a mandrel. The packer is supported on a packer support on the mandrel. As the packer is assembled, opposed lugs on the mandrel are placed in a J slot of a housing so that the packer is capable of being set by a wireline pressure setting assembly when the packer tool is positioned in the opening in a casing or in the open hole without requiring further manipulation of the packer tool. The J slot on the housing cooperates with the lugs on the mandrel in setting the packer tool, in releasing the packer tool and in enabling the packer tool to be converted for setting by a well string, or other operations.
The wireline-set tubing-release packer (also referred herein as the FM/WL tool) of the present invention, unlike the tool disclosed and claimed in the '547 patent to Morgan, does not require that it be converted for other uses. Further, the FM/WL tool of the present invention, unlike the tool in the '547 patent, utilizes multiple rotations to release the packer so that accidental release can be avoided, which may occur with the use of the J slot. Further, unlike the tool disclosed in the '547 patent, the invention does not require that the spring be compressed against the top slips when the tool is lowered downhole, but instead is in the fully expanded position prior to being utilized down hole. These and other features which will become apparent differentiate the present invention from the apparatus taught in the '547 patent.
Therefore, it is the principal object of the present invention to provide for a packer which provides for zone isolation, injection, pumping and production, which may be run on a wireline and set downhole, and released utilizing the tubing string and retrieved from the well;
It is a further object of the present invention to provide a simple and economical design of a packer for the above applications which does not require the ability to convert the tool for other uses;
It is a further object of the present invention to provide a packer having an easy-to-assemble design by incorporating a freely expanded spring member in a position so that there is no compression force against the spring member when the tool is being assembled;
It is a further object of the present invention to provide a means by which spring compression is achieved against the top slips, and to further increase the spring force to a predetermined amount during the setting action of the tool so that the top slips remain engaged during pressure reversals;
It is a further object of the present invention to provide a means which requires multiple rotations in order to release the packer to help prevent accidental release which could result if a J slot configuration was utilized.
What follows is a list of the features of the FM/WL Tool which provide for achieving the above-cited objects of the invention.
- Following setting of the FM/WL Tool on the wireline, the packer requires no tension or compression to hold the packer set.
- The FM/WL Tool and tubing can be retrieved in a single trip, since there is no seal assembly involved.
- The bore of the FM/WL Tool is the full tubing inner diameter.
- The rotational release, utilizing drop-away lugs, requires multiple rounds at the tool to release, which prevents accidental release when making tubing connection with a standard On Off tool.
- The threaded rotational release of the FM/WL Tool as expressed is protected from sand or other debris downhole.
- The positive lock-in following spring of the FM/WL Tool protects against premature release during pressure reversals.
- The FM/WL Tool by-pass opens before the upper slips release.
- The FM/WL Tool by-pass is below the upper slips so debris is washed from slips before release.
- A safety release is incorporated into the FM/WL Tool.
- The FM/WL Tool is pressure-rated from 6,000 to 10,000 psi.
- The FM/WL Tool can be run with tailpipe or TCP guns.
- The FM/WL Tool can be run in well under pressure and used as a temporary bridge plug, with several plugging options available.
- The FM/WL Tool accepts a wide variety of accessory items.
- The FM/WL Tool is ideal for wells requiring fiberglass tubing.
- When released the FM/WL Tool is stroked out to prevent swabbing effect.